Combustion system of a boiler with front and rear walls facing each other

Abstract

The invention discloses a combustion system of a combustion boiler whose front and rear walls face each other, comprising a primary fan, a secondary fan, an air preheater, a first coal mill, a second coal mill, a furnace, a The second direct flow nozzle, several first swirl burners, several second swirl burners, several third swirl burners and several burn-off air nozzles. The invention can effectively solve the problem of steam temperature control caused by water wall coking, high-temperature corrosion and low-nitrogen combustion caused by excessive oxygen deficiency in the reduction zone in the front and rear walls facing each other.

Description

technical field [0001] The invention belongs to the field of thermal power generation equipment, and relates to a combustion system, in particular to a combustion system for a combustion boiler whose front and rear walls oppose each other Background technique [0002] At present, the combustion methods in large pulverized coal combustion boilers mainly adopt four-corner tangential combustion and front and rear wall hedging combustion. Due to its advantages in combustion stability and heating surface layout, the front and rear wall opposed combustion boiler has become one of the main combustion methods used by supercritical and ultra-supercritical boilers. In the opposite combustion mode of the front and rear walls, the swirl burners are arranged on the water-cooled walls of the front wall and the rear wall of the furnace, and each burner organizes air distribution independently, and the flames are relatively independent; the flames of the burners on the same wall are separat...

AI Technical Summary

Problems solved by technology

[0004] Although air staged combustion technology can effectively reduce NO x emissions, but it also brings problems such as coking of the furnace water wall, high temperature corrosion, overheating and difficulty in controlling the main steam temperature, especially with the NO x Emission requirements are increasing day by day, in order to further reduce NO x Emissions, while reforming the burner in the original front and rear wall confrontation combustion method, the degree of air classification is continuously deepened, and the oxygen content in the main combustion zone and reduction zone is reduced, which makes the problems of coking, overtemperature and high temperature corrosion of the water wall more prominent

[0005] Although the industry improves the wall atmosphere near the water-cooled wall by adding wall-attached air to the front and rear wall opposed combustion boilers, there is still no effective way to simultaneously solve the water-cooled wall coking, high temperature corrosion and steam in the front and rear wall opposed combustion boilers. temperature control problem

Images